The present invention generally relates to flat panel displays. In particular, the present invention provides a displaying method, a display device, a color filter device and a display panel. More particularly, the present invention provides a displaying method performed by arranging certain color back lights and color filters for displaying, a related display device, a color filter device, and a resulting display panel.
In recent years, the visual display device of a personal computing electronic device has greatly improved concurrent with the development of the semiconductor elements and technologies. Until now, since the cathode ray tube (CRT) has a good display quality and low price, it has dominated the market of display device in these days. The CRT, however, has certain limitations. That is, since the CRT occupies a large space, has a heavy weight and consumes a great quantity of power, it is often not suitable for personal use or for connecting with several computer terminals. Moreover, it is also not suitable for a portable personal electronic device, which should be light, thin, small, and has low power consumption. Therefore, a thin film transistor (TFT) liquid crystal display (LCD) having characteristics of high image quality, minimum space requirement, low power consumption and low radiation is the trend in the display device market.
FIG. 1 is a schematic cross-sectional view of a basic structure of a conventional LCD, and FIG. 2 is a schematic top view of the LCD illustrated in FIG. 1. Referring to FIG. 1 and FIG. 2, the conventional LCD 100 is mainly constructed by a back light module 110 and a LCD panel 120. The LCD panel 120 is disposed over light exit plane 112 of the back light module 110. The LCD panel 120 is generally constructed by an active component array substrate 130, a color filter substrate 140, and a liquid crystal layer 150. The liquid crystal layer 150 is disposed between the active component array substrate 130 and the color filter substrate 140. The frame displayed by the LCD 100 is constructed by a plurality of array arranged pixels 160, wherein each pixel 160 comprises sub-pixels 162, 164 and 166 having red (R), green (G) and blue (B) color filters disposed thereon respectively. The color displayed by each pixel 160 is determined by the color of the light from the back light module 110 and the color of the color filters.
Most conventional LCDs use a matrix displaying method. In the matrix displaying method, a white light W is emitted from the back light module 110. After the white light W passes through the color filters of the sub-pixels 162, 164 and 166, red light R, green light G and blue light B are formed respectively. Meanwhile, the transmittance of the light of each of the sub-pixels 162, 164 and 166 is decided by the rotation angle of the liquid crystal therein. Therefore, the color displayed in each pixel 160 of the frame is determined by mixing the red light R, the green light G and the blue light B. FIG. 3 is a schematic view illustrating a displaying method of a conventional LCD. Referring to FIG. 3, the horizontal axis represents the space ratio of each color image, and the vertical axis represents the time ratio of each color image in a unit frame time. As shown in FIG. 3, it is noted that in the conventional displaying method, the space utility rate of each color image is only ⅓ since each color filter only occupies ⅓ space of each pixel.
In order to solve the problem, a color sequence displaying method has been developed. In the LCD using the color sequence method, the color filters are not required. In addition, the cold cathode fluorescence lamp tube (CCFL) of the back light module may emit red, green and blue color lights (i.e., three primary color lights), wherein these color lights may be switched rapidly. It is noted that, with the aid of the phenomenon of persistence of vision of the human eye, the LCD using the color sequence displaying method may display a full-color frame by switching each color image with high frequency. FIG. 4 is a schematic view illustrating another displaying method of a conventional LCD. Referring to FIG. 4, the horizontal axis represents the space ratio of each color image, and the vertical axis represents the time ratio of each color image in a unit frame time. As shown in FIG. 4, it is noted that, if the LCD using the color sequence displaying method has the same unit frame time as the conventional matrix displaying method, the switching frequency of each color light of the back light module shown in FIG. 4 must be three times of the scan frequency of the LCD using the matrix displaying method. Therefore, the design and manufacture of the LCD using the color sequence displaying method is often more difficult to achieve.
From the above, it is seen that improved techniques for displaying visual features is highly desirable.